Modern aircraft are provided with a windscreen which is quite strong and flexible. When the aircraft strikes a bird, with the bird impinging upon the windscreen, hopefully, the windscreen maintains integrity, even though flexing, to protect the pilot. However, sometimes the windscreen is broken and the pilot is subjected to harm from parts of the windscreen and from the onrushing air. In some aircraft, a headup display combiner is positioned on the pilot's line-of-sight. If the combiner remains in place, it provides some protection for the pilot. However, should windscreen structure or other masses such as the bird also impact the combiner, it is desirable for the combiner to move out of the way rather than shatter. The shattering of such a glass optical element would further risk the pilot. Thus, it is desirable to provide a combiner support structure which firmly holds the combiner in place until the combiner receives forces approaching those which would break up the combiner.